1. Field of the Invention
The present invention relates to a facsimile machine, which transmits and receives facsimile data via an Internet Protocol (IP) network by using the IP.
2. Description of Related Art
Recently, accompanying a spread of the Internet, various services using the Internet network are proposed. For example, a proposal is made on facsimile, which transmits and receives facsimile data via the Internet. Such facsimile is known Internet facsimile (hereinafter referred to as “IP-FAX”).
A private network can be configured by a plurality of terminal devices including the IP-FAX. When a remote IP-FAX or the like connected to the Internet accesses directly to the IP-FAX via a router, a global IP address of the router and a port number of the IP-FAX to be accessed become necessary.
Suppose that an IP-FAX is connected to a private network, and a remote device connected to the Internet accesses directly to the IP-FAX via a router. When the remote device inputs and transmits a Uniform Resource Locator (URL) of the router and a port number of the IP-FAX on the private network, the router receives a packet. In the router, a private IP address and the port number of the IP-FAX connected to the private network are previously stored by being associated with one another. When the router transmits the received packet to an IP-FAX having an IP address associated with a destination port number of the received packet, the IP-FAX can receive the packet transmitted from the remote device connected to the Internet.
When a plurality of IP-FAX having the same default port number are connected to a private network, although each of the IP-FAX has different private IP addresses, the IP-FAX have the same port number with one another. Therefore, a remote device connected to the Internet cannot access directly to the IP-FAX via a router. Conventionally, when an IP-FAX establishes a connection to a private network, or when a port number of an IP-FAX is necessary to be changed, the port number of the IP-FAX is changed. Then, an access is made to the router from a Web browser of a Personal Computer (PC) connected to the private network, and a setting of the port number in the router is changed.
Meanwhile, a World Wide Web (WWW) server and a mail server or the like, which are connected directly to the Internet, are previously assigned with a fixed IP address that does not overlap with one another. However, such an IP address is expressed by a decimal number and difficult to be distinguished by a person. Therefore, a Domain Name System (DNS) is used. Further, the DNS system manages a domain name and a host name, which can be distinguished easily by a person, by associating with an IP address. By designating a domain name or a host name and carrying out an inquiry by using the DNS system, the domain name or the host name can be converted into an IP address. Such DNS system is utilized widely in the current Internet.
However, in such a DNS system, a host name and an IP address of each terminal device are required to be associated one with another and registered previously in a database of a DNS server. The host name and the IP address of each terminal device to be registered are required to be fixed. In a private network system adopting a dynamic IP address method where an IP address changes each time when a connection is established with a network, the DNS system is difficult to be applied.
Therefore, in the private network system adopting the dynamic IP address method, an exclusive router is used as a communication terminal device. Further, the exclusive router includes a function for registering dynamic DNS (DDNS) information, which includes at least an IP address and a host name assigned to the exclusive router, in a DNS server for a dynamic IP, each time when the exclusive router accesses to a communication network.
As described above, conventionally, a router manages a port transfer setting of an IP-FAX. When a port number to be used by the IP-FAX is changed, a maintenance work is also required to be carried out at the router. That is, there exists a drawback that time is required for changing the port number registered in the router.
That is, the IP-FAX includes various server functions such as a Hyper Text Transfer Protocol (HTTP) server function for serving as a document management server, for example, to store a received facsimile document. The server functions are accessed from a remote device. Therefore, a plurality of ports are required to be set in the IP-FAX. When carrying out a port setting, maintenance work is required to be carried out at both the IP-FAX and the router. There exists a drawback that an extremely troublesome operation is required to be carried out.
When a new system is introduced to a private network and a port setting of the new system is necessary to be prioritized, a port setting of an IP-FAX is required to be changed. In this case, a port transfer setting of a router is also required to be changed, which can be troublesome.
Meanwhile, as described above, each time when a router is connected to a communication network, DDNS information, which includes at least an IP address and a host name assigned to the router, is required to be registered in a DNS server for the dynamic IP, and an exclusive router is used. However, recently, a broadband environment has already been established. If an exclusive router for the DDNS is provided, routers become redundant and a system becomes difficult to be constructed. Therefore, a consideration is made to provide a router function in a facsimile machine. However, if the router function is provided in a facsimile machine, there exists a drawback of an increase in the costs of the facsimile machine.